kein sounds

package com.muo.sound;

import com.muo.sound.R;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.media.MediaPlayer;


public class sound extends Activity {

    private Button playbutton;
    private MediaPlayer mp;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        playbutton = (Button)findViewById(R.id.playbutton);
        playbutton.setOnClickListener(new Button.OnClickListener() { 
            public void onClick (View v){ 
                mp = MediaPlayer.create(getBaseContext(), R.raw.testsound);
                mp.start();
            }
        });
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<Button
    android:id="@+id/playbutton"
    android:layout_width="87px"
    android:layout_height="wrap_content"
    android:text="Play"
    android:layout_x="40px"
    android:layout_y="182px"
    >
</Button>
    
</LinearLayout>